I thinbk the OP meant sound treatment.
At the stage you're at now, I'd say a good pair of monitors is more important(good doesn't equal expensive, some $100 8inch bookshelves hooked to a speaker amp will be better than nothing at all), but the "next step" immediately following monitors(if not at the same time, should be at least a little treatment to tame your room.
Right now Auralex is cheap!!!! Go for it!